/*
 * Copyright © 2011 Nokia Corporation. All rights reserved.
 * Nokia and Nokia Connecting People are registered trademarks of Nokia Corporation. 
 * Oracle and Java are trademarks or registered trademarks of Oracle and/or its
 * affiliates. Other product and company names mentioned herein may be trademarks
 * or trade names of their respective owners. 
 * See LICENSE.TXT for license information.
 */ 

package com.nokia.example.wordpress.networking;

import java.security.MessageDigest;

/**
 * Operation for loading gravatar icons from www.gravatar.com.
 */
public class GetGravatarOperation extends NetworkOperation {

    /**
     * Listener interface
     */
    public interface Listener {

        /**
         * Called when a gravatar has been loaded.
         * @param email Email address identifying the gravatar
         * @param data Image data
         */
        public void gravatarReceived(String email, byte[] data);
    }
    String email;
    Listener listener;

    /**
     * Constructor
     * @param listener
     * @param email Email identifying the gravatar to be loaded
     */
    public GetGravatarOperation(Listener listener, String email) {
        this.listener = listener;
        this.email = email;
    }

    /**
     * Starts the operation.
     */
    public void start() {

        StringBuffer hashcode = new StringBuffer();
        try {
            MessageDigest digest = java.security.MessageDigest.getInstance("MD5");
            byte[] emailbytes = email.getBytes();
            digest.update(emailbytes, 0, emailbytes.length);
            byte[] output = new byte[128];
            int out = digest.digest(output, 0, output.length);
            for (int i = 0; i < out; i++) {
                int num = output[i] & 0xff;
                if (num < 0x10) {
                    hashcode.append("0");
                }
                hashcode.append(Integer.toHexString(num));
            }
        } catch (Exception e) {
            throw new RuntimeException(e.getMessage());
        }

        // Request a smaller image than default, which is 80x80
        String url = "http://www.gravatar.com/avatar/" + hashcode + "?s=64.jpg";
        System.out.println("Gravatar url for " + email + " is " + url);
        Network nw = new Network(this);
        nw.startHttpGet(url);
    }

    /**
     * Calls the listener, no parsing needed here.
     */
    public void networkHttpGetResponse(byte[] data) {
        listener.gravatarReceived(email, data);
    }
}
